--- a/dom/media/MediaRecorder.cpp
+++ b/dom/media/MediaRecorder.cpp
@@ -278,18 +278,16 @@ class MediaRecorder::Session: public nsI
         mSession->Extract(false);
         nsCOMPtr<nsIRunnable> event = new ExtractRunnable(mSession);
         if (NS_FAILED(NS_DispatchToCurrentThread(event))) {
           NS_WARNING("Failed to dispatch ExtractRunnable to encoder thread");
         }
       } else {
         // Flush out remaining encoded data.
         mSession->Extract(true);
-        if (mSession->mIsRegisterProfiler)
-           profiler_unregister_thread();
         if (NS_FAILED(NS_DispatchToMainThread(
                         new DestroyRunnable(mSession)))) {
           MOZ_ASSERT(false, "NS_DispatchToMainThread DestroyRunnable failed");
         }
       }
       return NS_OK;
     }
 
@@ -414,17 +412,16 @@ class MediaRecorder::Session: public nsI
   friend class TracksAvailableCallback;
 
 public:
   Session(MediaRecorder* aRecorder, int32_t aTimeSlice)
     : mRecorder(aRecorder)
     , mTimeSlice(aTimeSlice)
     , mStopIssued(false)
     , mIsStartEventFired(false)
-    , mIsRegisterProfiler(false)
     , mNeedSessionEndTask(true)
     , mSelectedVideoTrackID(TRACK_NONE)
   {
     MOZ_ASSERT(NS_IsMainThread());
 
     uint32_t maxMem = Preferences::GetUint("media.recorder.max_memory",
                                            MAX_ALLOW_MEMORY_BUFFER);
     mEncodedBufferCache = new EncodedBufferCache(maxMem);
@@ -602,22 +599,16 @@ private:
   // Destroy this session object in the end of this function.
   // If the bool aForceFlush is true, we will force to dispatch a
   // PushBlobRunnable to main thread.
   void Extract(bool aForceFlush)
   {
     MOZ_ASSERT(NS_GetCurrentThread() == mReadThread);
     LOG(LogLevel::Debug, ("Session.Extract %p", this));
 
-    if (!mIsRegisterProfiler) {
-      char aLocal;
-      profiler_register_thread("Media_Encoder", &aLocal);
-      mIsRegisterProfiler = true;
-    }
-
     PROFILER_LABEL("MediaRecorder", "Session Extract",
       js::ProfileEntry::Category::OTHER);
 
     // Pull encoded media data from MediaEncoder
     nsTArray<nsTArray<uint8_t> > encodedBuf;
     mEncoder->GetEncodedData(&encodedBuf, mMimeType);
 
     // Append pulled data into cache buffer.
@@ -917,18 +908,16 @@ private:
   // handler. "mTimeSlice < 0" means Session object does not push encoded data to
   // onDataAvailable, instead, it passive wait the client side pull encoded data
   // by calling requestData API.
   const int32_t mTimeSlice;
   // Indicate this session's stop has been called.
   bool mStopIssued;
   // Indicate the session had fire start event. Encoding thread only.
   bool mIsStartEventFired;
-  // The register flag for "Media_Encoder" thread to profiler
-  bool mIsRegisterProfiler;
   // False if the InitEncoder called successfully, ensure the
   // ExtractRunnable/DestroyRunnable will end the session.
   // Main thread only.
   bool mNeedSessionEndTask;
   TrackID mSelectedVideoTrackID;
 };
 
 NS_IMPL_ISUPPORTS(MediaRecorder::Session, nsIObserver)